<template>
    <div class="cmt-container">
    <h3>发表评论</h3>
    <hr>
    <textarea placeholder="请输入要BB的内容（做多吐槽120字）" maxlength="120" v-model="msg"></textarea>

    <mt-button type="primary" size="large" @click="postComment">发表评论</mt-button>

    <div class="cmt-list">
      <div class="cmt-item" v-for="(item,i ) in cmts" :key="i">
        <div class="cmt-title">
         
          第{{ i+1 }}楼&nbsp;&nbsp;用户：{{ item.username }}&nbsp;&nbsp;发表时间：{{ item.add_time | dataFormat }}
        </div>
        <div class="cmt-body">
          {{ item.content }}
        </div>
      </div>

    </div>
  <!-- 声明一个方法 getMore ，在方法中调用getComments() -->
    <mt-button type="danger" size="large" plain @click="getMore">加载更多</mt-button>
  </div>
</template>

<script>
import { Toast } from 'mint-ui';
export default {
  data(){
    return {
      cmts:[], //自定义一个变量，接收后台获取到的数据
      msg:"",

    }
  },
  created() {
    // localStorage.clear()
    // this.getComments();
    this.cmts = JSON.parse(localStorage.getItem("cmt") || "[]");
  },
  methods: {
//获取后台数据
    getComments(){
      this.$http.get("comment.json").then(data => {
        if (data.body) {
          console.log(data.body);
          this.cmts = this.cmts.concat(data.body)// concat 拼接  将获取到的数据拼接到数组中
        } else{
          Toast("加载评论失败!!!!!!!!!!");
        }
      })
    },
    getMore(){
      this.getComments();
    },
    postComment(){
        //从本地存储中获取数据
        // JSON.parse()
      if(this.msg.trim() == "") return Toast("说点什么吧！！！！！！！");
      var newlist = JSON.parse(localStorage.getItem("cmt") || "[]");
      var obj = {id: new Date(),add_time:new Date(),username:"匿名用户",content: this.msg}
      newlist.unshift(obj);// 把评论信息添加到数组中
      // this.cmts = [...newlist,...this.cmts];//拼接俩个数组
      this.cmts = newlist;
      localStorage.setItem("cmt",JSON.stringify(newlist));//将数组存到本地存储中
      this.msg = "";
    }
  }
}
</script>

<style lang="scss" scoped>
.cmt-container {
  h3 {
    font-size: 18px;
  }
  textarea {
    font-size: 14px;
    height: 85px;
    margin: 0;
  }

  .cmt-list {
    margin: 5px 0;
    .cmt-item {
      font-size: 13px;
      .cmt-title {
        line-height: 30px;
        background-color: #ccc;
      }
      .cmt-body {
        line-height: 35px;
        text-indent: 2em;
      }
    }
  }
}
</style>